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Key departmental publications, e.g. annual reports, budget papers and program guidelines are available in our online archive.

Much of the material listed on these archived web pages has been superseded, or served a particular purpose at a particular time. It may contain references to activities or policies that have no current application. Many archived documents may link to web pages that have moved or no longer exist, or may refer to other documents that are no longer available.

Review of existing Red Fox, Wild Dog, Feral Cat, Feral Rabbit, Feral Pig, and Feral Goat control in Australia. I. Audit

Ben Reddiex, David M. Forsyth, Eve McDonald-Madden, Luke D. Einoder, Peter A. Griffioen, Ryan R. Chick, and Alan J. Robley.
Department of the Environment and Heritage, 2004

Results (continued)

7.4 Monitoring

7.4.1 Frequency of monitoring

Monitoring of any type (e.g., pest species or native species as defined by survey participants) was undertaken in between 22 and 56% of control actions across the six targeted species where survey participants had answered the monitoring questions (monitoring questions were answered in 82-96% of control actions across the six targeted pest species; Figure 7.24a). Monitoring of 'pest species' in Figure 7.24a included bait-take, despite the suitability of this technique as a population monitoring method being highly debatable (see Section 8). The frequency of control actions where monitoring was undertaken was highest for the three carnivore species (foxes, wild dogs and feral cats) with between 50 and 56% of control actions having some form of monitoring. The herbivore species only had between 22 and 26% of control actions with associated monitoring. For all species, no detailed information was available from the survey participants for some (<3%) control actions despite monitoring having been undertaken (these instances are omitted from subsequent analyses). When bait-take was discounted as a monitoring technique, the percentage of pest species monitored when foxes and wild dogs were targeted decreased to 32% and 31%, respectively (Figure 7.24b).

7.4.2 Monitoring categories

Of those control actions where monitoring had been conducted, the pest species category was the focus of monitoring (range 77-97% across all six pest animal species; Figure 7.25a). Monitoring of native species occurred in 54% of goat control actions where monitoring was undertaken, but ranged from 16-38% for all other species. Monitoring of resources or other types of monitoring occurred in <1% of fox control actions, and <3% of feral rabbit control actions. When bait-take was discounted as a monitoring technique for the three carnivore species (foxes, wild dogs and feral cats), the percentage of control actions that undertook pest monitoring decreased to 29, 51, and 65%, respectively (Figure 7.25b).

Figure 7.24. Percentage of control actions for each targeted pest species where monitoring was undertaken, a) where bait-take was classified as a monitoring technique, and b) where bait-take was not classified as a monitoring technique. Number of control actions per targeted pest species are shown on the figure.

Figure 7.24. Percentage of control actions for each targeted pest species where monitoring was undertaken, a) where bait-take was classified as a monitoring technique, and b) where bait-take was not classified as a monitoring technique. Number of control actions per targeted pest species are shown on the figure.

Figure 7.25. Percentage of control actions (only where monitoring was undertaken) where pest species, native species, or resources had been monitored for each of the targeted pest species, a) where bait-take was classified as a monitoring technique, and b) where bait-take was not classified as a monitoring technique. The number of control actions per targeted species are shown on the figure. Monitoring categories are not mutually exclusive.

Figure 7.25. Percentage of control actions (only where monitoring was undertaken) where pest species, native species, or resources had been monitored for each of the targeted pest species, a) where bait-take was classified as a monitoring technique, and b) where bait-take was not classified as a monitoring technique. The number of control actions per targeted species are shown on the figure. Monitoring categories are not mutually exclusive.

7.4.3 Types of monitoring

The monitoring techniques used varied according to whether pest animal species, native species or resources were being monitored. Survey participants reported that the main aim of pest animal monitoring was to assess the effectiveness of the control action, either by monitoring changes in the level of bait take during the period of the control action, and/or by monitoring changes in the relative abundance of the pest animal species. Bait take was primarily utilised for the carnivorous pest animal species, being undertaken in 75, 54 and 37% of actions where foxes, wild dogs and feral cats were targeted, respectively, but for only 10, 12 and 0% of actions where feral rabbits, feral pigs and feral goats were targeted, respectively (Figure 7.26). The high proportion of bait take monitoring for the carnivore species reflects the high proportion of baiting undertaken for these species where presence/absence of a bait can be recorded (e.g., buried 1080 baits whose fate is checked; see section 7.2.6), as opposed to poisoning of feral rabbits and feral pigs which often involves the widespread distribution of small baits. Sand pads were the main technique for assessing the relative abundance of carnivore species (range across species: 23-56%). Spotlight counts were the main technique for monitoring pest animals when feral rabbits were targeted (73%), followed by daylight counts (19%). Daylight counts and aerial surveys were the dominant monitoring techniques when feral pigs and feral goats were targeted.

The main aim of native species monitoring was to assess changes in native species/ecological communities abundance or condition following control of the targeted pest animal species. Techniques varied between the carnivore and herbivore species, largely due to broad differences in the objectives of control and the types of species that are threatened by the pest animal species (i.e., threatened species and habitat conservation were the main objectives for the predator and herbivore species, respectively; see section 7.2.3). Trapping for small mammals was the most common monitoring technique for native species, when foxes, wild dogs or feral cats were targeted (range 49-75%; Figure 7.27). In contrast, vegetation surveys were the dominant monitoring technique for native species when rabbits, pigs or goats were targeted (range: 50-84%). Trapping, daylight counts and aerial surveys were also relatively common for the herbivore species. For the few control actions (n=7) where monitoring was undertaken for production values (see section 7.4.2), the main type of monitoring for the herbivore species was vegetation surveys.

The location of pest animal control operations that did and did not conduct native species monitoring is illustrated in Figures 7.28-7.33. There are numerous areas within Australia where no native species monitoring of control operations is being undertaken.

Figure 7.26. Percentage of control actions for each of the targeted pest species where different techniques were used for monitoring 'pest species'. The total number of actions per targeted species where monitoring had been undertaken are shown on the figure.

Figure 7.26. Percentage of control actions for each of the targeted pest species where different techniques were used for monitoring 'pest species'. The total number of actions per targeted species where monitoring had been undertaken are shown on the figure.

Figure 7.27. Percentage of control actions for each of the targeted pest species where different techniques were used for monitoring of 'native species'. The number of actions per targeted pest species where native species monitoring had been undertaken are shown on the figure.

Figure 7.27. Percentage of control actions for each of the targeted pest species where different techniques were used for monitoring of 'native species'. The number of actions per targeted pest species where native species monitoring had been undertaken are shown on the figure.

Figure 7.28. Distribution of EPBC Act listed threatened native species threatened by foxes and location of fox control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.28. Distribution of EPBC Act listed threatened native species threatened by foxes and location of fox control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.29. Distribution of EPBC Act listed threatened native species threatened by wild dogs and location of wild dog control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.29. Distribution of EPBC Act listed threatened native species threatened by wild dogs and location of wild dog control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.30. Distribution of EPBC Act listed threatened native species threatened by feral cats and location of feral cat control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.30. Distribution of EPBC Act listed threatened native species threatened by feral cats and location of feral cat control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.31. Distribution of EPBC Act listed threatened native species threatened by rabbits and location of rabbit control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.31. Distribution of EPBC Act listed threatened native species threatened by rabbits and location of rabbit control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.32. Distribution of EPBC Act listed threatened native species threatened by feral pigs and location of feral pig control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.32. Distribution of EPBC Act listed threatened native species threatened by feral pigs and location of feral pig control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.33. Distribution of EPBC Act listed threatened native species threatened by feral goats and location of feral goat control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

Figure 7.33. Distribution of EPBC Act listed threatened native species threatened by feral goats and location of feral goat control actions in 2003 (electronic distributions supplied by ERIN, DEH, Canberra). Black open circles represent operations with no native species monitoring, and pink crossed circles represent operations that conducted native species monitoring. Size of circles represents area (km2). Some actions directly overlay other actions.

7.4.4 Monitoring evaluation

A key objective of this project was to evaluate the effectiveness of control activities in terms of the outcome of control, and for changes in threatened species abundance and recovery of native species/ecological communities (see Section 3). The first step in carrying out such an evaluation is to assess whether the monitoring and experimental design that was undertaken was sufficient to address the objectives of the control action.

For all objectives of control (i.e., threatened species, habitat conservation, and production values), it is important to know whether the control action actually reduced the abundance of the pest species (i.e., monitoring of targeted pest species). Similarly, for the objectives threatened species and habitat conservation, in addition to the response of the targeted species, the response of resources (native species or ecological communities) to the control action is required (i.e., monitoring of native species). For the objective 'production values', in addition to monitoring of the targeted pest species, the response of production values to the control action is also required (i.e., monitoring of production values).

7.4.4.1 Control action objectives

The following results are for the control actions where survey participants answered the monitoring questions, and some form of monitoring had been undertaken (i.e., only 31% of all control actions across all species). When the objective of control was for threatened species, for all carnivore species between 21 and 32% of control actions had monitored both pest and native species (irrespective of whether pre-control, post-control or pre- and post-control monitoring had been undertaken; Figure 7.34). A similar pattern was evident when feral rabbits and feral pigs were targeted for the objective of threatened species, with only 4 and 17% of control actions respectively monitoring both pest and native species, but 65% of feral goat actions had assessed both pest and native species (Figure 7.34; note the small control action sample sizes for some of the targeted pest species). When bait-take was omitted as a monitoring technique, the only significant change occurred for foxes. The number of actions when both pest and native species had been monitored declined from 65 to 42, when the objective was threatened species, and from 18 to 10 when the objective was habitat conservation.

When the objective of control was habitat conservation, a similar pattern was evident to that outlined for the threatened species objective (Figure 7.34). Only feral goats (32%) had >17% of control actions where monitoring of both pest species and native species was conducted. Feral rabbits were the only targeted species where both pest species and production values were monitored (17% of control actions where monitoring was conducted; Figure 7.34).

To further evaluate whether the objectives of control actions could be reliably addressed with the observed monitoring and experimental designs (see Section 5), we assessed whether the correct types of monitoring were undertaken pre-and post-control and whether non-treatment areas were monitored. Pre- and post-control monitoring is required for pest species in order to assess the degree to which the control action reduced the abundance of the pest species, and for native species to assess the degree of change in abundance/condition of resources resulting from a control action. The inclusion of non-treatment areas lead to substantial increases in the reliability of inferences from control actions (see Section 5)

Figure 7.34. Percentage of control actions (only where some monitoring had been undertaken) for each targeted species where the correct monitoring types (see below) required to assess the control action objectives had been undertaken. For the threatened species and habitat conservation objectives both pest and native species monitoring was required; and for the production values objective, both pest species and resources monitoring was required. The number of actions per targeted species for each control objective are shown on the figure. Objectives are not mutually exclusive.

Figure 7.34. Percentage of control actions (only where some monitoring had been undertaken) for each targeted species where the correct monitoring types (see below) required to assess the control action objectives had been undertaken. For the threatened species and habitat conservation objectives both pest and native species monitoring was required; and for the production values objective, both pest species and resources monitoring was required. The number of actions per targeted species for each control objective are shown on the figure. Objectives are not mutually exclusive.

For all species and monitoring categories (i.e., pest and native species), the majority of monitoring was undertaken post-control actions (range across pest species 50-87%; range across native species 25-84%; Figure 7.35). Non-treatment areas were rarely assessed when pest species were monitored (for all pest animal species targeted <15%; Figure 7.35), but occurred at a higher rate when native species were monitored (Figure 7.35). Monitoring designs rarely contained random sampling of monitoring items (Figure 7.35).

For all control actions where some form of monitoring was undertaken, only three control actions (2 targeting foxes, and 1 targeting feral rabbits) had undertaken the required monitoring types to reliably address the objective of the pest animal control (i.e., for the threatened species objective, both pest species and a resource (native species) must have been monitored both pre-and post-control, and the monitoring also had to be undertaken in non-treatment areas (Table 7.5).

Table 7.5. Number of actions for each control objective that had undertaken the correct monitoring types (see below), and had pre-and post-control monitoring for both monitoring types, monitored non-treatment areas for both monitoring types, and both. For the threatened species and habitat conservation objectives, both pest and resources (native species) must have been assessed. For the production values objective, both pest species and production values must have been assessed. The total number of actions per objective, and the total number of actions where some monitoring was undertaken are shown on the figure.
    All Actions Monitoring undertaken Monitoring design Experimental design  
Objective Species targeted   Any type Correct types Pre- and-post control Non-treatment areas Both pre- and post-control and non-treatment areas
Threatened species              
  Fox 689 280 66 15 7 2
  Dog 178 64 20 1 3 0
  Cat 91 28 6 5 0 0
  Rabbit 812 122 5 0 0 0
  Pig 58 6 1 0 0 0
  Goat 75 17 11 0 0 0
Habitat conservation              
  Fox 162 109 18 2 3 0
  Dog 96 25 4 0 3 0
  Cat 23 4 1 0 0 0
  Rabbit 892 160 19 0 2 11
  Pig 155 27 3 0 0 0
  Goat 147 34 11 0 0 0
Production values              
  Fox 160 90 0 0 0 0
  Dog 144 77 0 0 0 0
  Cat 3 1 0 0 0 0
  Rabbit 54 24 4 11 3 11
  Pig 57 15 0 0 0 0
  Goat 19 12 0 0 0 0

1 One control action had both habitat conservation and production values as the objective of control.

Figure 7.35. Percentage of control actions (only where some monitoring had been undertaken) for each targeted pest species, and for each of pest and native species monitoring where pre-control, post-control or pre-and post-control monitoring was undertaken, non-treatment areas were assessed, and random sampling was undertaken. The total number of actions per target species for each monitoring characteristic are shown on the figure.

Figure 7.35. Percentage of control actions (only where some monitoring had been undertaken) for each targeted pest species, and for each of pest and native species monitoring where pre-control, post-control or pre-and post-control monitoring was undertaken, non-treatment areas were assessed, and random sampling was undertaken. The total number of actions per target species for each monitoring characteristic are shown on the figure.

7.5 Non-survey data

All States and Territories of Australia have agricultural focused organisations that are involved in technology transfer of pest animal control techniques and distribution of baits, and in some instances undertake control operations. It is possible to collate the quantity of poison baits supplied to farmers/landholder groups for each State and Territory. In Queensland, the DNRME supplied us with bait usage in each shire from 1999 to 2003 for foxes, wild dogs, feral rabbits and feral pigs. None of the other States or Territories provided us with this information.

Other significant control operation data that we are aware of, but was not used in this review include; dog control programmes conducted in three regions of Victoria over at least the last 10 years (the data supplied was unsuitable for inclusion in this review), and dog control operations in the Northern Territory (no data supplied).